Ex vivo measures of LDL oxidative susceptibility predict carotid artery disease

The purpose of the study was to assess whether ex vivo measures of low-density lipoprotein (LDL) oxidation improved prediction of carotid artery disease (CAAD) case-control status compared to standard lipid and smoking measures. Methods: One hundred and forty cases with a high degree of carotid artery stenosis aged 40–83 years and an equal number of controls without stenosis or other vascular disease were matched by censored age within 2 years. Matched logistic regression evaluated the significance of copper-induced oxidative measures with and without covariates. The relationship of LDL oxidation measures with statin use and current smoking was also evaluated. Results: Logistic regression demonstrated a significant effect of the three correlated measures of oxidative susceptibility (lag time, oxidation rate and maximal rate of oxidation) separately on disease prediction (all p < 0.05). These oxidative measures remained significant predictors of case-control status when other cardiovascular disease predictors (age; LDL-C, HDL-C and ApoAI levels; current smoking, ever smoking and pack-years smoked) were jointly considered. This relationship was not attributable to the effects of statin use on LDL oxidation. Conclusions: Ex vivo measures of oxidation improved the prediction of carotid artery disease status, suggesting that this is an important determinant of atherosclerotic risk in this older population.